Q and A

Question

Is a negative HIV test four weeks after PEP okay?

7 June 2023. Related: All topics, HIV testing, PEP/PEPSE, Southern Africa.

Good day.

Is it possible to test positive after testing negative after completing 28 day of PEP?

Answer

Answer: Simon Collins

Hi

In the UK, people need to wait 4 to 6 weeks after the last dose of PEP before taking a 4th generation HIV antigen/antibody test.

If this test is negative after 6 weeks, then someone is told they do not have HIV. If it is negative after 4 weeks, it means HIV is unlikely, but that a second test should confirm this after a few more weeks.

There is no point taking an HIV test as soon as you finish PEP.

This is because the PEP could just be covering up or delaying a potential infection.

This answer was updated in June 2023 from a question first posted in November 2020. This is because UK guidelines now recommend testing after 6 weeks rather than after 4 weeks.

Please see this link for more information about PEP:
https://i-base.info/qa/factsheets/pep-faq

Simon.

281 comments

  1. Aarif •

    Hi sir
    Today my 45of the day I’ll do test in hiv combo test???
    And pep complete 28day
    My first does Dec 8
    My last does January 04
    Today January 19
    So I do the test results is 0.06
    It’s conclusion test plz tell me plz !!!!!!

  2. Josh Peasegood •

    Hi Sli, do you know the viral load of your partner? When someone is on treatment with a viral load below 200/undetectable it is impossible to pass on HIV via sex. This is true even without a condom.

    This is called U=U. It means that when someone has an undetectable viral load, HIV is suppressed so much by treatment in the body that it is impossible to pass on.

    U=U:https://i-base.info/u-equals-u/

  3. Sli •

    Hello Doc, My partner is positive and on ARVs. On 19/11/23 the condom broke while having sex, How true is it that when I urinate during sex I won’t get infected? We did not have sex after that in 2months. After that I took a test and it was negative. Should I be worried about it because I did this test under 3 months?

  4. Josh Peasegood •

    Hi Peter, for more information about transmission please see here: https://i-base.info/qa/factsheets/hiv-transmission-and-testing

  5. Peter •

    My friend slept with a posive person and then the friend slept with another person… Can the 3rd person get the virus

  6. Josh Peasegood •

    Hi Simon, for information about testing please see here: https://i-base.info/qa/factsheets/hiv-transmission-and-testing

  7. Simon •

    Hi, I finished PEP yesterday and ran a test afterwards.The test was negative but I’m not sure if it’s a 4th generation test.So I asked my clinic and they said “ The facility uses the standard national algorithm for HIV testing.”

    They went on to say “The test modality is supported by global partners including the WHO and the US CDC. It is reliable and inline with international best practices”. Do ibhavw any chances of of not catching the virus?

  8. Josh Peasegood •

    Hi Rio, yes this test is conclusive. You do not have HIV and require no further tests.

    Please see here for more information: https://i-base.info/qa/factsheets/hiv-transmission-and-testing

  9. Rio •

    Oral hiv antibody test after 8 months is conclusive

  10. Josh Peasegood •

    Hi Jomon, your test result is conclusive. You do not have HIV.

    The swollen lymph nodes you are experincing and the white tongue is not caused by HIV. Please speak with your doctor for further investigation and management.

    For information about testing and transmission please see here: https://i-base.info/qa/factsheets/hiv-transmission-and-testing